Mulling apparatus



y 14, 1940- w. F. PIPER MULLING APPARATUS 3 Sheets-Sheet 1 ll 00%: no

May 14, 1940 w. F. HPER MULLING APPARATUS Filed Sept. 14, 1936 3 Sheets-Sheet 2 May 14, 1940. w. F. PIPER MULLING APPARATUS Filed Sept. 14, 1936 3 Sheets-Sheet 3 Patented May 14, 1940.

UNITED STATES MULL'ING APPARATUS Walter F. Piper, Oak Park, 111., aaaignor to The Beardsley & Piper Company, Chicago, 111., a-

, corporation of Illinois Application September 14, 1938, Serial No. 100,630

17 Claims.

The present invention relates generally to apparatus for mulling or mixing granular material.

' More particularly the invention relates to that type of mulling apparatus which is adapted to 5 mull, mix or recondition molding sand and comprises a frame, an open top sand retaining receptacle which is mounted on and supported by the frame and embodies a substantially flat circular bottom and an annular outwardly bulged 10 side wall, and a plurality of balls which are adapted through the medium of a motor and speed reducing gearing to be driven in a circular course around the side wall of the receptacle and operate during travel or propulsion in said course to effect mulling, mixing or reconditioning of the sand in the receptacle.

One object of the invention is to provide a mulling apparatus of this type, which not only is an improvement upon and more efllcient than previously designed apparatus for the same purpose but also operates to mull the material more uniformly and expeditiously.

Another object of the invention is to provide a mulling apparatus of the type and character under consideration in which the mulling balls have solid rubber coverings which during drive and spinning of the balls grip the sand-yieldingly and elastically and as a result operate to effect by a squeezing action an extremely quick and ready mulling, mixing or reconditioning of the sand in the receptacle and also to increase the capacity of the apparatus as a whole.

A further object of the invention is to provide a ball type mulling apparatus which includes cross head supported and driven scrapers behind the balls for scraping the sand from the inner face of the outwardly bulged side Wall of the receptacle and moving the sand inwards on the receptacle bottom, and also includes cross head scrapers for deflecting the sand outwards into the paths of the balls and not only effecting a secondary mulling action but also causing the material to'be so controlled that the entire batch thereof is subjected to mulling by each ball during each revolution of the ball driving cross-head.

Other objects of the invention and the various advantages and characteristics of the present mulling apparatus will be apparent from a consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the conclusion hereof.

In the drawings which accompany and form a supported and driven deflectors behind the part of this specification or disclosure and in which like numerals of reference denote corresponding parts throughout the several views:

Figure 1 is a view partly in plan and partly in horizontal section of a mulling apparatus embodying the invention;

Figure 2 is a vertical longitudinal section taken on the line 22 of Figure 1 and showing the grrangement and construction of the, mulling alls;

Figure'3 is a fragmentary vertical transverse section illustrating the construction and design of the scrapers and the deflectors;

Fdigure 4 is a perspective of one of the scrapers; an

Figure 5 is a perspective of one of the deflectors. v

I The apparatus which is shown in the drawings constitutes the preferred embodiment of the invention. It is primarily adapted for use in a foundry or like establishment in connection with the mulling, mixing, or reconditioning of molding sand, and comprises as the main or essential parts thereof a frame 6, a sand holding or retaining receptacle 1, and a pair of mulling balls 8.

The frame 6 is preferably of twopiece design and consists of a cast metal base section 9, and a cast metal top section l0. The base section 9 is elongated and embodies at one end thereof a bed plate II for an electric motor i2. At its other end the base section 9 embodies a continuous wall l3 which extends upwardly and to gether with the top section I of the frame defines a gear compartment M. The top section l0 embodiesa top wall l and a depending continuous wall [6. The latter rests on the wall l3 of the base section 9 and is secured in place by I means of bolts l'i which, as shown in Figures 2 and 3 extend through out-turned abutting flanges ill on the abutting margins of the two frame sections.

The sand holding or retaining receptacle 1 is mounted on and supported by the frame 8 and consists of a bottom iii, a side wall 20, and an upstanding tubular member 2!. is circular and rests on the top wall 55 of the 'top section l0 of the frame 6. Bolts 22 extend through the marginal portion of the top wall l5 andinto the receptacle bottom l9 and serve to hold the receptacle in fixed relation with the frame. The tubular member 2! is centrally dis posed with respect to the side wall 20 and is formed integrally with the bottom IS. The lower end of said tubular member is flared andembodies a substantially quandrantally curved outer The bottom l9 surface 23 which joins the top face of the bottom and serves to direct the sand which accumulates in, or works toward, the central portion of the receptacle outwards onto the receptacle bottom l9. The side wall 20 of the receptacle is substantially semicircular in cross-section and joins the top face of the receptacle bottom IS in a gradual curve. The cross-sectional diameter of the side wall is slightly greater than the diameter of the mulling balls 8. An infunclibular or funnel-shaped mouth 24 is formed integrally with and extends outwardly and upwardly from the upper margin of the side wall 20 and serves to receive sand and direct it into the receptacle for mulling purposes. Preferably the receptacle is in the form of a metallic casting.

The mulling balls 8 are preferably two in number. They comprise metallic cores 25 and solid rubber coverings 28. The cores 25 are spherical and are either hollow or solid depending upon whether light or heavy mulling balls are desired. The rubber coverings 26 are of uniform depth or thickness throughout and operate during drive of the balls, as hereinafter described, to grip the sand in the receptacle yieldingly and elastically. Because of the yielding or elastic character of the rubber coverings the sand is squeezed only and not pulverized for ground. Another ad'- vantage in employing rubber coverings for the balls resides in the fact that wear is reduced to a minimum and the bonding material which is mixed with the molding sand is uniformly mixed into bonding relation with the grains of sand. A further advantage in the use of rubber covered mulling balls resides in the fact that the sand is gripped frictionally and hence the balls do not skid and cause the sand to build up to any appreciable extent in front of them and be pushed around the receptacle without being subjected to any mulling action. By using rubber covered balls as distinguished from metal surfaced balls which tend to skid over the sand when the surfaces thereof become polished the capacity of the apparatus as a whole is materially increased. When .the apparatus is at rest the balls 8 rest on the receptacle bottom l9, as shown in Figure 2. When the apparatus is set in motion, that is, operated for sand mulling purposes, the balls are propelled or driven in a circular course around the side wall 20 of the receptacle and not only swing outwards towards the receptacle side wall in response to the action of centrifugal force but also spin. As a result of the outward thrust of the balls and the spinning action the sand between the balls and the receptacle side wall together with the sand on the outer marginal portion of the bottom of the receptacle is effectively mulled, that is, squeezed and the bonding material thus uniformly distributed over the grains of sand. Propulsion or drive of the balls 8 in a circular course around the side wall 20 of the receptacle is effected by means of a revolvable crosshead 21. The latter is in the form of an inverted letter S. It extends horizontally across the cen- "'tral portion of the receptacle and is fixedly connected, as hereinafter described, to the upper end of a vertically extending shaft 28 which extend: through the tubular member 2i of the receptacle 1 and is driven from the electric motor l2 by means of speed reducing gearing in the gear compartment M. The end portions of the crosshea/d extend around and behind the mulling balls 8, as shown in Figure 1, and are provided at the outer extremities thereof with a pair of vertically extending forks 29. The latter are arranged in substantially parallel relation due to the curva- I ture of the end portions of, the cross-head and support a pair of vertically extending pivot pins 30. In order to impart a rotary movement from the cross-head 21 to the mulling balls rollers 3| are provided. These rollers are two in number and are mounted on the pivot pins 30 as shown in Figure 1. The pins extend through the bifurcations of the forks 29, as shown in the drawings, and are suitably secured against axial displacement with respect to the forks. The rollers 3| engage the rear portions of the balls and, as shown in Figure 2, are disposed mid-way between the top and bottom portions of the balls. During drive or rotation of the cross-head 21 the rollers swing around the receptacle and due to their contact with the balls cause the latter to travel in a circular course around or within the receptacle side wall. Due to the fact that the rollers are mounted on the vertical pivot pins 30 they are free to revolve on vertical axes and hence permit the mulling balls to spin without any retardance due to contact with the rollers. The rollers are positioned outwardly of the ball centers, that is, between the sidewall of the receptacle and the centers of the balls. By so positioning the rollers the mulling balls are driven without any wedging action and with a minimum amount of power. Preferably the cross-head is in the form of a metal casting.

-The upper end of the vertically extending shaft 28 is provided with a polygonal stem 32 and embodies a shoulder 33 beneath the stem. As shown in Figure 2, the stem fits within a polygonal socket 34 in the central portion of the crosshead 21 and forms a driving connection between the shaft and the cross-head whereby when the shaft is driven the cross-head together with the mulling balls 8 is rotated bodily within the receptacle 1. The central portion of the cross-head 'rests on the shoulder 33 and is locked in place by means of a cap 35 which overlies the central portion of the cross-head and is clamped or urged in a downward direction by means of a bolt 36 which extends through the cap 35 and fits within an internally threaded socket in the polygonal stem 32. The upper end of the shaft 28 is journaled in a roller bearing 31 and the lower end of the shaft is supported and journaled in a roller bearing 38. The bearing 31 consists of an outer race within the upper end of the upstanding tubular member 2| of the receptacle 1, an inner race around the upper end of the shaft 28, and an annular series of rollersbetween the two races. The races and rollers of the bearing 31 are arranged and constructed so as to hold the shaft against upward axial displacement-with respect to the tubular member 2|. The roller bearing 38 is constructed and arranged to hold the shaft 28 against downward axial displacement and consists of an outer race within a hub-like mem* ber 39 on the base section 9 of the frame 6, an inner race around the lower end of the shaft 28 and an annular series of rollers between the two races. The hub-like member 39 is disposed in the gear compartment l4 and is formed as an integral part of the base section 9 of the frame. The speed reducing gearing which serves to drive the shaft 28 from the electric motor l2 consists of a bevel pinion 48, a bevel gear 4|, a pinion 42, and a gear 43. The bevel pinion 40 is mounted on one end of a horizontally extending shaft 44. The latter is journaled in suitable roller bearings within a sleeve 45 between the base and top sections of the frame and is connected by a the frame. The pinion 42 is keyed or otherwise fixedly secured to the shaft 41 and is disposed between the bevel gear 4| and the roller bearing 48. The gear 43 is fixed to the lower end of the shaft 28 and meshes with and is driven by the pinion 42. When the motor I! is supplied with current it operates through the medium of the speed reducing gearing within the gear compartment l4 to drive the shaft 28 which in turn swings or rotates the cross-head 21 and the mulling balls 8.

In order to eifect aeration, a secondary mulling of the sand within the receptacle 1, and also to control the sand so that the entire batch is subjected to the action of each mulling ball 8 dur-,

ing each revolution of the cross-head 21; a pair of scrapers 50 and a pair of deflectors 5| are provided.

The scrapers are located directly behind the mulling balls 8 and serve during drive of the cross-head 21 to scrape the mulled sand from the inner periphery or face of the outwardly bulged side wall of the receptacle and to project the sand inwardly toward the central portion of the receptacle bottom I9. They are connected for conjoint rotative movement with the crosshead 21 by means of angle brackets 52 and lugs 53 and comprise scraping parts 54 and sand projecting parts 55. Preferably the scrapers are in the form of plate metal stampings. The scraping parts 54 are positioned adjacent to the outwardly bulged side wall 20 of the receptacle and have their outer edges shaped conformably to the inner periphery or face of said receptacle side wall. As shown in Figures 3 and 4, the scraping parts of the scrapers extend from the bottom l9 of the receptacle to the funnel-shaped mouth 24 and are curved or rounded so that during drive or operation of the apparatus they scrape the mulled sand from the inner face of the outwardly bulged side wall 20 of the receptacle and direct it toward the sand projecting parts 55. The latter extend inwardly and rearwardly with respect to the lower ends of the scraping parts 34 and overlie the receptacle bottom l9. They project approximately at 45 angles with respect to the scraping parts and operate to project or direct the scraped mulled sand toward the central portion of the receptacle bottom. The lugs 53, which with the angle brackets 52 serve to connect the scrapers 50 to thecross-head 21, are formed integrally with the cross-head and project rearwardly and at substantially right angles with respect to the roller supporting forks 29. The brackets 52 extend between the lugs and the scrapers 50 and embody horizontally extending legs 52 and vertically extending legs 52'. The

legs 52 abut against the bottom faces of the lugs 53 and are secured to the lugs by means of rivets 58. The vertically extending legs 52' are formed integrally with and depend from the outer ends of the legs 52 and are riveted or otherwise fixedly secured to the central portionsv of the scraper parts 54 of the scrapers.

The deflectors 5| are located behind the scrapers I0 and extend outwardly from a cylindrical skirt 58 on the central portion of the crosshead 21. They are preferably in the form of plate metal stampings and are secu ed to the cross-head 2'! bylugs 51 and tongues 58. The lugs, as shown in Figure 1, are formed integrally with and project rearwardly from the inner portions of the end parts of the cross-head 21 and are spaced inwardly from the lugs 53 for the scrapers 50. The deflectors extend upwardly from the receptacle bottom l9 to a point adjacent to the mouth 24 of the receptacle and are curved so that they serve to deflect or project the sand outwards into the path of the mulling balls. The tongues 58 are formed integrally with the deflectors and are bent so that they extend forwardly at right angles thereto. They underlie the bottom faces of the lugs 51 and are secured to the e lugs by means of rivets 59. The outer portions of the deflectors are curved, as shown in Figure 1, and terminate a sufficient distance from the outwardly bulged side wall of the receptacle so that the sand which is deflected outwards by thedeflectors is directed onto the outer margin of the receptacle bottom and also against the side wall of the receptaclef The deflectors coact with the scrapers to effect a secondary mulling of the sand and in addition operate to confine the mulling balls against forward movement towards the inner ends of the sand projecting parts 55 of the scrapers when the cross-head 21 is brought to rest or stopped at the completion of a mulling operation. The outer or curved end portions of the deflectors are so angularly disposed that during operation of the apparatus they cause the sand in connection with the secondary mulling action to move gradually around the receptacle in the direction of rotation of the cross-head. The skirt 56 from which the deflectors project substantially radially is formed as an integral part of and depends from the central portion of the integral part 51 and surrounds and forms a protector for the upper end of the tubular member 2| of the sand retaining receptacle 1. When the apparatus is operated at a normal speed, say 90 R. P. M., the deflectors due to their size and shape fling the sand outwards against the side.

wall of the receptacle and effect aeration of thesand. By reason of the fact that the deflectors extend from the tubular member 2| to a point slightly inwards of the side wall of the receptacle the sand is so controlled that the entire batch is subjected to the action of each mulling ball during each revolution of the cross-head 21, and hence the sand is uniformly mulled. Aeration of the sand is attributable to the fact that the deflectors project the sand outwards in a scattered manner and the sand is maintained in more or less suspension prior to being squeezed by the mulling balls.

When it is desired to mull sand with the apparatus, the sand to be mulled is shoveled or otherwise delivered into the mouth 24 of the open top receptacle 1. The mouth, ashereinbeiore described, serves to direct the sand into the central portion of the receptacle. When the electric motor I2 is started by supplying it with electric current, the shaft 28 is driven through the medium of the speed reducing gearing in the gear compartment I4 and in turn drives the cross-head 21 and the mulling balls 8.. During drive of the cross-head the mulling balls as a result of contact with the rollers 3i move in a circular'course around the inside'of the receptacle and in response to centrifugal force move I outwards toward the outwardly bulged side wall 20 of the receptacle and mull the sand between them and said side wall of the receptacle. During drive of the balls around the receptacle the balls spin or rotate and effect the desired mulling of the sand on the-receptacle bottom and Wi hin the receptacle side wall. Because the balls are slightly less in diameter than the cross-sectional diameter of the side wall 20' of the receptacle, the balls when flung or moved outwards in response to centrifugal force move upwards out of contact with the receptacle bottom. The inner portions of the balls, however, revolve in spaced relation over the receptacle bottom and effect mulling of the sand on the outer portion of the receptacle bottom. Whereas the sand on the outer portion of the receptacle bottom is not subjected to the weight or outward thrust of theballs proper mulling is effected due to the fact that the balls in spinning thereover during travel ina circular course therearound press or force the grains of sand together. Because of the use of rollers at the ends of the cross-head the balls are free to ride or move upwards as they move outwards and center themselves with respect to the outwardly bulged receptacle side wall. The sand which is compressed against the inner face of the outwardly bulged side wall of the recep tacle as the result of the action of the mulling balls 8 is scraped clear 'of the receptacle side wall and directed inwards toward the center of the receptacle bottom by the action of the scrapers 50. After being directed inwards the sand encounters the deflectors EI and is projected outwards in a scattered manner into the path of the balls. The apparatus is driven until the sand within, the receptacle is mulled to the proper extent. At the conclusion of the mulling opera-- tion the sand is removed in any suitable manner from the receptacle. By reason ofthe fact that outward movement of the mulling balls I and the resultant mulling effect is due to centrifugal force it is manifest that when the apparatus is driven at a high rate of speed a more aggressive and quicker mulling action is obtained than when the apparatus is driven at a lower speed and the mulling balls, due to the reduced centrifugal action, are flung or moved outwards against the outwardly bulged side wall of the receptacle with less force. Because the mulling action is attributable to centrifugal force and not the weight of the mulling balls the balls need not be extremely heavy. I

The herein described mulling apparatus occupies but a small amount of space considering its capacity and may be manufactured at a comparatively low and reasonable cost. It operates to mull a batch of sand in an exceptionally short period of time and not only is extremely efficient in operation due to the secondary mulling action of the scrapers and deflectors but also effects a uniform mulling of the sand and necessitates the use of but a small quantity of bonding material.

Although the apparatus has been described as being adapted primarily for use in a foundry in connection with mulling, mixing or reconditioning molding sand, it is to be understood that the apparatus may also be used to mull or condition materials other than sand and of either plastic or semi-plastic character. It is also to be understood that the invention is not to be restricted to the details set forth, since these may be modified within the scope of theappended claims, without departing from the spirit and scope of the invention.-

Having thus described the invention what-I claim as new and desireto. secure by Letters Patent is:

1. In a mulling apparatus of the character described, thecomblnation of an open top receptacle adapted to contain the material to be mulled and comprising a substantially flat circular bottom and an annular outwardly bulged side wall extending in a' curved manner upwardly and outwardly and then inwardly from the outer marginal portion of the bottom, a freely rotatable mulling element in the receptacle arranged to travel in a circular course around said side wall and adapted during such travel to. spin or roll and to squeeze the material between it and said side wall and thus effect mulling of said material, means for propelling the element in said circular course, and means propelled by said means conjointly with the element for controlling the material so that during each time the element travels around the side wall the entire mass of material is flung outwards in a scattered and aerated manner against substantially all portions of the inner face of said side wall into the path of the element and is then after squeezing and resultant'mulling by the element scraped and deflected inwards.

2. In an apparatus for mulling molding sand, the combination of an open top receptacle adapted to contain a batch of sand to be mulled and comprising a substantially flat circular bottom and an annular outwardly bulged side wall extending in a. curved manner upwardly and outwardly and then inwardly from the outer marginal portion of the bottom, a freely rotatable mulling ball with an elastic outer surface arranged to travel in a circular course around said side wall and adapted during such travel to spin or roll and to squeeze the sand between it and said side wall and thus effect mulling of said sand, means for propelling the ball in said circular course, and means propelled by said means conjointly with the ball for controlling the sand so that during each time the ball travels around the side wall substantially the entire batch of sand is flung outwards in a scattered and aerated manner against substantially all portions of theinner face of said side wall into the path of the ball and is then after squeezing and resultant mulling by the ball scraped and deflected inwards.

3. In a mulling apparatus ofthe.v character described, the combination of an open top receptacle adapted to contain the material to be mulled and comprising a substantially flat circular bottom and an annular outwardly bulged side wall of substantially semicircular cross-section, joined by a gradual curve to the outer margin of the bottom and extending outwardly and upwardly and then inwardly, a freely rotatable mulling ball of slightly less diameter than the cross-sectional diameter of the side wall, arranged to travel in a circular course around the side wall and adapted during such travel to spin or roll and to squeeze the material between it and said side wall and thus mull said material, means for propelling the mulling ball in said circular course, and means propelled by said means conjointly with the ball 4. In an apparatus for mulling molding sand, the combination of an open top receptacle adapted to contain a batch of sand to be mulled and comprising a substantially flat circular bottom and an annular outwardly bulged side wall of substantially semicircular cross-section, joined by a gradual curve to the outer margin of the bottom and extending outwardly and upwardly and then inwardly, a freely rotatable mulling ball of slightly less diameter than the cross-sectional diameter of the side wall and with an elastic outer surface, arranged to travel in a circular course around the side wall and adapted during such travel to spin or roll and to squeeze the sand between it and said side wall and thus mull saidv sand, means for propelling the mulling ball in said circular course, and means propelled by said means conjointly with the ball for controlling the sand so that during each time the ball travels around the side wall substantially the entire mass or batch of sand is flung outwards in a scattered and aerated manner against all portions of the inner face of said side wall and is then after squeezing and resultant mulling by the ball scraped and deflected inwards.

5. In a mulling apparatus of the character described, the combination of an open top receptacle adapted to contain the material to be mulled and comprising a substantially flat circular bottom and an annular outwardly bulged side wall extending upwardly from the outer margin of the bottom, a mulling ball with an outer facing of elastic friction material arranged to-trav'el in a 1 circular course around the side wall of the receptacle and adapted during such travel to spin or roll and to squeeze with substantially no pulverizing the material between it and said side wall and thus effect mulling of said material, means for propelling 'the ball in said circular course, and means propelled by said means conjointly with the ball for directing the material so that it moves outwards against substantially all portions of the receptacle side wall for squeezing by the ball.

6. In a mulling apparatus of the character described, the combination of an open top receptacle adapted to contain the material to be mulled and comprising a substantiallyflat circular bottom and an annularvoutwardly bulged side wall joined to and extending upwardly from the outer margin of the bottom, a mulling ball in the form of a metallic core and a spherical solid rubber stantially no pulverizing the material between it and said side wall and thus efiect mulling of the material, means for propelling the mulling ball in said circular course, and means propelled by said means conjointlywith the ball for controlling the material so that during each time the ball travels around the side wallsubstantially the entire mass of material is flung outwards in a scattered and aerated manner against all por tions of the inner face of said side wall and is then after squeezing and resultant mulling by the ball scraped and deflected inwards.

7. In a mulling apparatus of the character described, the combination of an open top receptacle adapted to contain the material to be mulled and comprising a substantially fiat circular bottom and an annular outwardly bulged side wall oi! substantially semicircular cross-section, joined by a gradual curve to the outer margin of the bottom and extending outwardly and upwardly and then inwardly, a freely rotatable mulling ball in the form of a metallic core and a spherical solid rubber covering and of slightly less di: ameter than the cross-sectional diameter of the side wall, arranged to travelin a circular course around the side wall of the receptacle and adapted during such travel to spin or roll and move outwards in response to centrifugal force into substantially centered relation with the side wall and squeeze with substantially no pulverizing the material between it and said side wall and thus and comprising a substantially flat circular bottom and an outwardly bulged side wall of substantially semicircular cross section extending outwardly and upwardly and then inwardly from the outer margin of the bottom, a freely rotatable mulling ball of slightly less diameter than the cross-sectional diameter of the side wall arranged to travel in a circular course around the side wall and adapted during such travel to spin and to move outwards in response to centrifugal force into centered relation with said side wall and thus effect mulling of the material'between it and said side wall, and means for propelling the mulling ball in said circular course comprising a power driven rotary cross-head in the central portion of the receptacle and a substantially horizontally extending ball engaging roller connected to the outer portion of the cross-head and arranged to engage the rear portion of the ball at a point outwardly of the central part of the ball.

9. In a mulling apparatus of the character described, the combination of a receptacle adapted to contain the material to be mulled and comprising a circular bottom and an annular side wall extending upwardly from the outer margin of the bottom, a. rotary mulling element adapted to travel in a circular course around the interior of the receptacle side wall and during such travel to spin orroll and to squeeze the material between it and said side wall and thus to effect mulling of said material, a deflector mounted for conjoint travel with the mulling eiemeritland arranged and designed to deflect and scatter the entire mass of material in the receptacle outwardly against/substantially all portions of the side wall and into the path of and for squeezing by the element each timeit completes said circular course, and'means for propelling the mulling. element and deflector in the aforementioned course.

10. In a mulling apparatus of the character described, the combination of a receptacle adapt-. ed to contain the material to be mulled and comprising a substantially flat circular bottom and an outwardly bulged side wall joined by a gradual curve to the inner margin of the bottom and extending upwardly and outwardly and then inwardly, a freely rotatable mulling ball in the receptacle arranged 'to travel in a circular course around thesidewall of said receptacle and adapted during such .travel to spin or roll and to squeeze the material between it and said side wall and thus efiect mulling of said material, means for propelling the ball in said circular course comprising a power driven rotary cross-head extending across the central portion of the receptacle, and a deflector in front of the ball connected to rotate with the cross-head and shaped and designed so that it extends upwards from the receptacle bottom to substantially the top margin of the outwardly bulged side wall and from substantially the central portion oi. the receptacle to the side walland operates during each rotation of the cross-head to deflect and scatter the entire mass of material outwardly against all portions of said side wall and into the path of, and for squeezing by, the ball.

11. In a mulling apparatus of the character described, the combination of a receptacle adaptelement in said circular course, and means for controlling the material so that during each time the element travels around said side wall the entire mass of material is projected outwards against substantially all portions of the side wall and into the path of the mulling element and is then, after mulling by said element, scraped from the side wall, comprising a deflector connected for conjoint travel with, and disposed directly in front of, the element and arranged and designed so that it extends upwardly from the receptacle bottom to substantially the top of the side wall and operates in conjunction with outward projection of the material so to scatter the material that pronounced aeration takes place, and a scraper disposed behind and also connected for conjoint travel with the element and having a trailing part shaped to deflect the scraped mulled material inwards towards the central portion o the receptacle.

12. In a mulling apparatus of the character described, the combination of a receptacle adapted to contain the material to be mulled and comprising a circular bottom and an outwardly bulged sidewall extending upwardly from the outer margin of the bottom, a freely rotatable mulling ball in the receptacle arranged to travel in a circular course around the side wall and adapted during such travel to spin or roll and to squeeze the material between it and said side wall and thus effect mulling of the material, means for propelling the ball in said circular course, and means for controlling the material so that each time the ball travels around the receptacle side wall substantially the entire mass of material is projected outwards against sub-' stantially all portions of the side wall and into the path of the ball and is then after mulling by the ball scraped from-said side wall, comprising a deflector disposed directly in front of and connected for conjoint travel with the mulling ball and designed and constructed so that in connection with outward projection of thematerial it operates so to scatter the material that pronounced aeration takes place, and a scraper disposed directly behind and also connected for conjoint travel with the ball and shaped conformably to the side wall and so that the trailing part thereof operates to direct the mulled material inwards towards the central portion of thereceptacle. I

. 13. In an apparatus for mulling molding sand,

the combination of a receptacle adapted to contain a batch of molding sand to be mulled and comprising a substantially flat circular bottom and an annular outwardly bulged side wall of substantially semicircular cross-section extending upwardly from the outer margin of the bottom, a freely rotatablemulling ball in the receptacle arranged to travel in a circular course around the side wall and adapted during such travel to spin or roll and to squeeze the sand between it and said side wall and thus eilect mulling of the sand, means for propelling the ball in said circular course comprising a motor driven rotary crosshead extending across the central portion of the receptacle, and means for controlling the sand in the receptacle so. that during each time the ball travels around the side wall substantially the entire mass of sand is projected outwards against substantially all portions of the side wall and into the path of the ball 'andlis then after mulling by the ball scraped from said side wall, comprising a deflector in front of the ball connected to the cross-head for conjoint rotation therewith and shaped and designed so that it extends upwards from the receptacle bottom to substantially the top of the side wall and operates in connection with outward projection of the sand so to scatter the sand that pronounced aeration of the latter occurs, and a substantially semicircular scraper directly behind the ball connected to the cross-head for conjoint rotation therewith and having the trailing portion thereof shaped to deflect the mulled sand inwardly toward the central portion of the receptacle.

14. In a sand mulling apparatus of the charreceptacle adapted'to contain a batch of molding sand to be mulled and comprising a circular bottom and an annular outwardly bulged side wall extending outwardly and upwardly and then inwardly from the margin of the bottom,- a plurality of freelyrotatable balls arranged to travel in a circular course around the side wall and adapted during such travel to spin or roll and to squeeze the sand between them and said side wall and thus effect mulling of the sand, means for propelling the balls in said circular course comprising a rotary power driven cross-head extending across the central portion of the receptacle, a plurality of angularly disposed scrapers corresponding in number to and disposed directly in front of the balls and connected to the crosshead for conjoint rotation therewith and arranged and-designed so that they extend from the receptacle bottom to substantially the top of the receptacle side wall and operate to project the entire batch or mass of sand in the receptacle outwards in a finely scattered stream against substantially all portions of the side wall and into the path of the balls, and a plurality of curved scraperscorresponding in number to and disposed behind the balls and connected for conjoint rotation with the cross-head and having the leading portions thereof shaped and arranged to scrape the mulled sand from the side wall and the trailing portions thereof shaped so as to direct the sand inwards in a suspended manner into contact with thedeflectors.

15. A mulling apparatus comprising in. comranged to travel in a circular course around said side wall and adapted during such travel to spin or roll and to squeeze the material between it and said side wall and thus efiect mulling of said material, means for propelling the element in said circular course, and means propelled by said means conjointly with the element for controlling the material so that during each time the element travels around the side wall the entire mass of material is flung outwards in a scattered and aerated manner against substantiallyall portions of the inner face of said side wall and into the path of the element and is then after squeezing and resultant mulling by the element scraped and deflected inwards.

16. A mulling apparatus comprising in combination a bowl shaped receptacle adapted to contain the material to be mulled and embodying a substantially flat circular bottom and an annular'side wall extending upwardly from the outer margin of the bottom, a freely rotatable mulling element with an outer tread or facing of elastic friction material arranged to travel in a circular course around the receptacle side wall and adapted during travel to move outwards in response to the action of centrifugal force and in addition to spin or roll and to squeeze with substantially no pulverizing the material between it and said side wall and thus efiect mulling of the material, means for propelling the element in said circular course, and means propelled by said means conjointly with the element for directing the material so that it moves outwards against said side wall and into the path of the element for squeezing by the latter.

17. A mulling apparatus comprising in combination a bowl shaped receptacle adapted to contain the material to be mulled and embodying a circular bottom and an annular side wall extending upwardly from the outer margin of the bottom, a. freely rotatable mulling element with an outer tread of elastic friction material arranged to travel in a circular course around the side wall of the receptacle and adapted during such travel to move outwards in response to centrifugal force and also to spin or roll and to squeeze with substantially no pulverizing the material between it and said side wall and thus effect mulling of the material, a deflector mounted for conjoint travel with the mulling element and arranged and designed to deflect and scatter the entire mass of material in the receptacle outwardly against substantially all portions of the side wall and into the path of and for squeezing by the element each time it completes such circular course, and means for propelling the mulling element and deflector in the aforementioned course.

WALTER F. PIPER. '0 

